© 2008 Plant Management Network.
Variety and N Management Effects on Grain Yield and Quality of Winter Barley
Ariel Castro, Departmento de Producción Vegetal, Estación Experimental Dr. Mario A. Cassinoni, Facultad de Agronomía, Universidad de la República, Ruta 3, km 363, Paysandú 60000, Uruguay; Steven Petrie, Superintendent, Columbia Basin Agricultural Research Center, Oregon State University, P.O. Box 370, Pendleton, OR 97801; Al Budde, Cereal Crops Research Unit, USDA-ARS, 501 N. Walnut Street, Madison, WI 53705; Ann Corey, Patrick Hayes, and Jennifer Kling, Barley Project, Department of Crop and Soil Sciences, Oregon State University, Crop Science 253, Corvallis, OR 97331; and Karl Rhinhart, Farm Manager, Columbia Basin Agricultural Research Center, Oregon State University, P.O. Box 370, Pendleton, OR 97801
Corresponding author: Steven Petrie. firstname.lastname@example.org
Castro, A., Petrie, S., Budde, A., Corey, A., Hayes, P., Kling, J., and Rhinhart, K. 2008. Variety and N management effects on grain yield and quality of winter barley. Online. Crop Management doi:10.1094/CM-2008-1125-01-RS.
Winter malting barley (Hordeum vulgare L.) is a potential alternative crop for the dryland region of the Pacific Northwest. Nitrogen fertilization can increase grain yield but may also increase lodging and grain protein and reduce test weight. The objectives of this research were to determine the effect of N application rate and timing on grain yield and quality of winter feed and malting barley varieties. Field trials were conducted at Pendleton, OR (17 inches annual precipitation) and Moro, OR (12 inches annual precipitation). Nitrogen was applied at 0, 50, 100, or 150 lb N per acre in the fall and at 0 or 50 lb N per acre in the spring at Pendleton and at 0, 30, 60, or 90 lb N per acre in the fall and at 0 or 30 lb N per acre in the spring at Moro. Nitrogen fertilization increased grain yields at Pendleton to a maximum of 5,800 lb/acre in 2001 and 5,200 lb/acre in 2002 and at Moro to a maximum of 3,000 lb/acre. Nitrogen fertilization increased grain protein and reduced test weights. Yields of the advanced lines of malting barley were about 90% of the yields of feed type barley varieties. Spring N applications did not increase grain yield or protein more than fall N applications.
Production of winter habit malting barley (Hordeum vulgare L.) grown in the Pacific Northwest (PNW) of the United States would offer maltsters and brewers an alternative supply of grain while offering PNW growers an alternative and potentially valuable winter cropping option. The PNW is characterized by warm, dry summers and cool, wet winters; northeastern Oregon receives 75% of its annual precipitation between October 1 and May 1. This winter precipitation pattern means that yields of winter barley can be as good as, or better than, yields of irrigated spring barley (1,2,8). Winter barley is usually the first cereal crop harvested in the PNW; harvest begins in early- to mid-July, well before other areas of the country.
Two key issues affecting the production of winter malting barley in the PNW are the availability of approved varieties and the development of nitrogen management recommendations to ensure that these varieties achieve their yield potential while not exceeding acceptable grain protein levels. Winter malting barley varieties are being developed by the barley breeding program at Oregon State University but there is no information on the effect of N management practices on grain yield and quality.
Grain protein content is a key factor in malting quality, with a minimum level required to ensure adequate enzyme level and yeast nutrition. However, excessive protein creates difficulties in the malting process. The desired level for malting barley grain protein is between 11.5 and 13.5%. Somewhat lower grain protein levels are usually specified for malting barley exported to other countries.
Nitrogen management is the key tool used to manage grain protein. Nitrogen management recommendations for dryland spring and winter feed barley are available for the Palouse region of northern Idaho and eastern Washington (6,7) and irrigated winter barley in southern Idaho (3). Most dryland cropping in the PNW consists of a summer-fallow/winter-cereal sequence. Nitrogen fertilizer is usually applied as anhydrous ammonia in the late spring or early summer during the fallow phase. However, split applications of N may result in more accurate N application rates because growers are better able to predict the yield potential of the crop by late winter or early spring when they have more information about the crop-year precipitation. Unfortunately, results from irrigated hard winter wheat research indicate that split applications of N often result in higher grain protein levels than pre-plant N applications (5). Spring N applications are often taken up and used more efficiently by the plant, thereby increasing the likelihood of producing high protein grain (4). However, these studies were conducted under irrigated conditions where leaching of N is more likely to occur than under dryland cropping conditions where rainfall limits crop yield.
The objectives of this research were to determine the effect of N application rate and timing on grain yield and quality of advanced lines and varieties of winter feed and malting barley.
Variety and N Rate and Timing Design
Three field trials were conducted in the 2000-2001 and 2001-2002 growing seasons; two were located at the Pendleton Station (45.7°N, 118.6°W) while one was at the Sherman Station at Moro (45.5°N, 120.6°W) of the Columbia Basin Agricultural Research Center, Oregon State University. These trials will be referred to by location and harvest year (e.g., Pendleton 2001). Soil at both locations is a Walla Walla silt loam (coarse, mixed, mesic, Typic Haploxeroll). Average annual precipitation is 17 inches at the Pendleton station and 12 inches at Moro; 75% of the precipitation occurs between 1 October and 1 May.
The Pendleton 2001 trial included four adapted varieties (Strider, Scio, Kold, and 88Ab536) and five advanced lines [Kold/88Ab536-68 (Kab 68), Strider/88Ab536-7 (Stab 7), Strider/88Ab536-47 (Stab 47), Strider/88Ab536-113 (Stab 113), and Strider/88Ab536-171 (Stab 171)]. The Pendleton 2002 and Moro 2002 trials included three varieties (Hundred, Kold, and Strider) and three advanced lines (Stab 7, Stab 47, and Stab 113). Hundred, Kold, Scio, and Strider are feed types and the other lines were potential malting varieties. The trials were seeded on 16 October 2000 and 2 October 2001 at Pendleton and 11 October 2001 at Moro at 22 seeds/ft² after tillage-based summer fallow. Analysis of soil samples collected prior to planting in the top four feet of the soil revealed a total of 144 lb of N (NO3 + NH4) at Pendleton 2001, 68 lb of N at Pendleton 2002, and 76 lb of N at Moro 2002.
A randomized complete-block split-split plot design was used at Pendleton 2001 with fall N rates as main plots, spring N rates as split plots and varieties as split-split plots. A randomized complete block design was used at Pendleton 2002 and Moro 2002. All trials had four replications. Fall N rates were 0, 50, 100, and 150 lb N per acre at Pendleton and 0, 30, 60, and 90 lb N per acre at Moro. Fall N was applied as anhydrous ammonia at Pendleton 2001 and as urea at Pendleton 2002 and Moro 2002. Spring N was applied as urea at 0 or 50 lb N per acre at Pendleton and 0 or 30 lb N per acre at Moro when the plants were in the late tillering stage of development. The plots were harvested using a plot combine, test weight was determined (2002 crops only), and grain protein was measured (malting lines only). The statistical analysis of the data was performed using the general linear models (GLM) procedure in SAS (SAS Institute Inc., Cary, NC) and each year and site was analyzed separately.
Field Studies on the Effects of Variety and N Management on Feed and Malting Barley
Rainfall at Pendleton in the 2000-2001 growing season was approximately normal (16.5 inches) but was only 79% of normal (13.0 inches) in the 2001-2002 growing season. Moro received only 75% of normal rainfall (8.4 inches). In addition, the precipitation during the fallow phase of the crop cycle was less than normal at Moro and the total crop cycle (fallow year + crop year) precipitation received by the Moro 2002 trial was only 65% of the mean crop cycle precipitation. These unusually dry conditions reduced yields compared to long-term average yields at Moro.
The ANOVA results revealed that varieties were a significant source of variation for all traits in all experiments. Fall N application significantly affected grain yield in the two trials at Pendleton, grain protein in all trials, and test weight in two trials (Table 1). There were few variety × N interactions; fall N × variety interactions were observed for test weight at Pendleton in 2002 as were spring N × variety interactions for test weight at both Pendleton and Moro in 2002.
Table 1. Summary of ANOVA results for the agronomic traits in the Pendleton 2001, Pendleton 2002, and Moro 2002 trials.
*, **, *** = significant at the 0.05, 0.01, and 0.001 probability levels, respectively.
x “—” = data not collected.
Average yields of the malting lines were less than the average yields of the feed type varieties at Pendleton, but not Moro (Table 2). The average yield of the three malting lines at Pendleton 2002 was 4,400 lb/acre compared to an average yield of 5,480 lb/acre for the three feed varieties.
Table 2. Grain yield of winter barley varieties at Pendleton 2001, Pendleton 2002, and Moro 2002.
x “—” = data not collected.
Increasing N application rate increased grain yield at Pendleton both years, consistent with the results from similar studies with winter wheat (5) (Fig. 1). Grain yield was greatest in 2001 when 100 lb/acre was applied. Grain yield in 2002 was less responsive to N application and yields were similar when 100 lb N per acre or more was applied. The larger yields and greater response to N at Pendleton in 2001 compared to 2002 can be plausibly attributed to the greater rainfall that was received during the 2000-2001 growing season compared to the 2001-2002 growing season even though the preplant soil test N was greater in 2000 than in 2001. Grain yield was affected by the application rate but not the time of application; for example, application of 50 lb N per acre resulted in approximately the same grain yield whether the N was applied prior to planting or in the spring at Pendleton. The winter rainfall (31 October to 1 March) was only 4.6 inches and we assume that this amount of rain was insufficient to leach the N below the rooting zone. Preplant N application at Moro 2002 had no effect on grain yield while spring N applications greater than 50 lb N per acre reduced yield. We assume that the unusually dry conditions at Moro limited the response to N fertilizer.
We found that varieties had significantly different grain protein in all trials (Table 1). Fall and spring N applications significantly increased grain protein in all trials and no interactions were detected between fall and spring N applications. These results contrast with other work showing that spring N applications are more effective at increasing grain protein (5). There was a significant fall N × variety interaction at Moro 2002. Averaged across malting lines, there was a linear grain protein response to increasing N application (Fig. 1) at Pendleton in both years. In contrast to grain yield, grain protein continued to increase as the N application rate increased at Pendleton for treatments that received either fall or fall and spring applications. The grain protein response at Moro 2002 was not linear and grain protein did not increase when more than 60 lb N per acre was applied preplant. However, grain protein exhibited a linear response to N when N was applied in the fall and spring.
The grain protein level of all varieties increased as the fall N rate increased but the slope and regression lines were only significantly different at Pendleton 2001 (Fig. 2). Stab 171 and 88Ab536 were more responsive to fall N than the other lines in the study. Stab 113 had the lowest protein levels while Stab 47 had the highest protein level at three of the four N rates. Grain protein did not exceed the AMBA specifications for any variety even at the highest N application rate.
There was a highly significant variety effect (P > 0.001) on test weight at Pendleton and Moro in 2002 (Table 1). The effect of fall N on test weight was highly significant (P > 0.001) at both locations while the effect of spring N was significant only at Pendleton. There was also a highly significant fall N × variety interaction at Pendleton but not Moro and a highly significant spring N × variety interaction at Pendleton and Moro. Test weights were lower at Moro than Pendleton. The differential response of six representative varieties to increasing fall N at Pendleton is shown in Figure 3. Increasing the fall N application rate reduced the test weight of Hundred while it increased the test weight of Stab 113 and had no effect on the test weight of Stab 47.
Summary and Conclusions
Varieties were a highly significant source of variation in grain protein in all experiments, underscoring the importance of variety selection. Yield of the most productive malt types of winter barley were about 93% of the yield from Strider feed type winter barley indicating that improved winter malting barley lines may be economically competitive with feed types of winter barley when grown in the intermediate rainfall areas of northeastern Oregon.
The maximum grain yield in these trials resulted from the application of 100 or 150 lb N per acre at Pendleton and the timing of application had little impact on grain yield. Application of higher rates of N reduced yield although there was no lodging in any of the trials. Grain protein increased with increasing N application rate in all trials. There was no fall N × spring N interaction on grain protein indicating that fall and spring N applications were equally effective at increasing grain protein.
These results indicate that fall and early spring N applications had similar effects on the grain yield and protein which may have important implications for N management options. The ability to apply a portion of the total N prior to planting and the remaining N in the spring may offer growers the opportunity to more accurately apply N fertilizer because they will know the amount of winter rainfall as well as the stored soil moisture when the spring N is applied. This result needs to be confirmed in additional field trials.
We thank the Oregon Agricultural Experiment Station, Oregon Grains Commission, Busch Agricultural Resources, and USDA-ARS Cereal Crops Research Unit for their support of this research.
1. Karow, R., Marx, E., McDonald, S., Bafus, R., Bohle, M., Eldredge, E., Hayes, P., Peterson, J., Reed, G., Shock, C., and Smiley, R. 2000. Winter grain varieties for 2000. Spec. Rept. 775. Oregon Agric. Expt. Stn., Oregon State Univ., Corvallis, OR.
2. Bassinette, J. P., Karow, R., McDonald, S., Rhinhart, K., Bafus, R., Bohle, M., Clark, D., Eldredge, E., Hayes, P., Peterson, J., Rykbost, K., Shock, C., Petrie, S., and Smiley, R. 2001. Spring grain varieties for 2001. Spec. Rept. 986. Oregon Agric. Expt. Stn., Oregon State Univ., Corvallis, OR.
3. Brown, B. D. 2006. Southern Idaho fertilizer guide: Irrigated winter barley. Current Info. Ser. No. 1082. Univ. of Idaho, Moscow, ID.
4. Brown, B., Westcott, M., Christensen, N., Pan, B., and Stark, J. 2005. Nitrogen management for hard wheat protein enhancement. Pacific Northwest Ext. Publ. 578. Washington State Univ., Pullman, WA.
5. Brown, B. D., and Petrie, S. E. 2005. Irrigated hard winter wheat responses to fall, spring, and late season applied nitrogen. Field Crops Res. 96:260-268.
6. Mahler, R., and Guy, S. 2006. Northern Idaho Fertilizer Guide – spring barley. Current Info. Ser. No. 920. Univ. of Idaho, Moscow, ID.
7. Mahler, R., and Guy, S. 2006. Northern Idaho Fertilizer Guide – winter barley. Current Info. Ser. No. 954. Univ. of Idaho, Moscow, ID.
8. Petrie, S. E., Hayes, P., Rhinhart, K., Corey, A., Kling, J., and Blake, N. 2003. Nitrogen management for optimum winter malting barley yield and quality. Agron. Abstr. ASA-CSSA-SSSA, Madison, WI.